Answer:
Following are the solution to the given points:
Explanation:
For point (a) :
In this, two points are exclusive to one another, it is a probability that first or the second project will have breaches,
![\to P = P(A) + P(B)](https://img.qammunity.org/2022/formulas/mathematics/college/cfb8b182ibztdbq8mksinazfpwj25h8pnn.png)
![= 0.3 + 0.25\\\\= 0.55](https://img.qammunity.org/2022/formulas/mathematics/college/ik3ssoik2wzhw5ehqix7fu83pz7ub90qk3.png)
Since the p(A & B)=0 is mutually exclusive.
For point (b):
![\to P = ( (1 -p(A)) * P(B))/(((1-P(A)) * P(B) + P(A&B))) \\\\](https://img.qammunity.org/2022/formulas/mathematics/college/a36bkf29016e5psxawc9wsh8e65ungf74u.png)
![= ((1 -0.3)* 0.25)/((1-0.3)*0.25 + 0) \\\\ = 1](https://img.qammunity.org/2022/formulas/mathematics/college/6thh5pg7m8elhvbufyhwa18qey28o02f3k.png)
For point (c):
if both a and b are independent:
(a):
![P = P(A) + P(B) - P(A)* P(B) \\\\](https://img.qammunity.org/2022/formulas/mathematics/college/ceejn1asiy1e4pw1vck4yrt7atji7bdnfw.png)
![= 0.3 + 0.25 - 0.3 * 0.25\\\\ = 0.475](https://img.qammunity.org/2022/formulas/mathematics/college/7ex0ymh72f5c6463ujy6u02oq31axs6msb.png)
(b):
![P = ((1 -p(A)) * P(B))/(((1-P(A)) *P(B) + P(A&B))) \\\\](https://img.qammunity.org/2022/formulas/mathematics/college/cib916vsdyzfn1rtgmr5lnlyfgzc9bmqv3.png)
![= ((1 - 0.3)* 0.25)/(((1-0.3)*0.25 + 0.3*0.25))\\\\ = 0.7](https://img.qammunity.org/2022/formulas/mathematics/college/rcgad791jzw61tnkqqw712u51bho6eg1ns.png)